Robot Arm to Grab Robotic Ship -- A Space Station First

For the first time, a robotic arm attached to the International Space Station (ISS) will capture an unmanned spaceship for docking on Thursday. The bus-size Japanese H-II Transfer Vehicle, or HTV, was launched on its maiden flight September 10. The remote-control ship is carrying more than four tons of equipment, food, clothes, and other essentials for the six astronauts currently aboard the space station.
Thursday, the craft should reach the correct position for the station's Canadian-built robotic arm, Canadarm2, to reach out and berth the Japanese ship.

With NASA's space shuttle program due to retire next year, experts say unmanned supply ships like the HTV will become crucial to maintaining the space station.

"This flight represents a significant step for Japanese space industry, by demonstrating key technologies that will benefit the station for many years to come," said Masazumi Miyake, deputy director of the Japan Aerospace Exploration Agency (JAXA) offices in Houston, Texas.

What's more, the success of the HTV may very well have a direct impact on the orbiting outpost's ultimate lifespan. Due to budget concerns, the ISS is currently slated to be deorbited in 2015.

The HTV's robotic-arm approach may prove to be a simpler, cheaper docking system than those used by existing European and Russian cargo ships, opening the door for a possible extension of the station's mission.

Cosmic Catch

Since 2000 unmanned Russian Progress craft have been supplementing shuttle missions to the space station. The ships bring up cargo, take on waste, then detach and eventually disintegrate in Earth's atmosphere.

In 2008 the European Space Agency sent up its first Automated Transfer Vehicle (ATV), dubbed Jules Verne, to add to the delivery system. (Watch video of Jules Verne burning up as it reenters Earth's atmosphere.)

Both the Russian and European supply ships dock themselves directly to entry hatches using complicated and expensive guidance and thruster technology.

By contrast, the HTV will use its GPS and laser guidance systems to gingerly inch itself to within 30 feet (9.1 meters) of the underbelly of the orbiting facility.